Final answer:
To find the new volume of a balloon after adding 4 g of oxygen to the existing 8 g, you convert the mass of oxygen to moles and use the molar volume of oxygen to determine the increase in volume. Since the mass is doubled, the volume proportionately increases, assuming temperature and pressure remain constant.
Step-by-step explanation:
The question involves finding the new volume of a balloon when additional oxygen gas is added, given the amount of oxygen in grams. Since gases are involved, this falls within the realm of Chemistry, and more specifically, relates to the concept of the molar volume of a gas at standard temperature and pressure (STP). To solve this, one must use the molar mass of oxygen (32 g/mol) to convert the mass of oxygen to moles. For oxygen gas (O₂), the molar volume at STP is 22.4 liters per mole. Therefore, adding 4 g to the already existing 8 g of oxygen in the balloon simply doubles the amount of oxygen as the original 8 g corresponds to 0.25 moles (8 g / 32 g/mol = 0.25 moles). So, 4 g will be another 0.125 moles. Since the volume of the gas is directly proportional to its amount (moles), doubling the amount of gas at constant temperature and pressure doubles the volume. If the original balloon with 8 g (0.25 moles) had a volume V, then adding another 4 g will make it 1.5×V because you are adding half the amount of the original oxygen gas again (from 0.25 to 0.375 moles)